The shame, Chuck, is that you are letting someone get to you, badly.

The shame is that I went out of my way to be courteous to this guy,
despite a long history of contentious conversations, and to treat him
very professionally when he sought my help. The shame is that five
years later he chooses to capitalize on his relatively unique position
("I've met this shyster in person!") to launch a campaign of flame
throwing and crap slinging based on some out-of-the blue accusations of
dishonest dealing. None of the many comments he posted to this same NG
following his trips to Seattle contained anything except glowing
remarks about his experiences when dealing with me.

Whether he was lying then or lying now doesn't really matter. His own
words prove that he is a far bigger liar than most people could ever
aspire to become.